Search results for " Thin Films"

ELECTRODEPOSITION OF NOVEL POLY(NAPHTHALENEDIIMIDE-QUATERTHIOPHENE) THIN FILMS AND APPLICATIONS IN PLASTIC OPTOELECTRONICS DEVICES

2013

A novel symmetric naphthalenediimide-quaterthiophene derivative (NDIT4d) has been polymerized on different substrates including glassy carbon and ITO/PET electrodes by means of electrochemical methods. XPS and UV-VIS spectroscopy as well as cyclic voltammetry have been employed for characterizing the thin film chemical features, the band gap and the HOMO and LUMO levels. DFT computational studies were in close agreement with the experimental observables also showing intriguing geometrical effects on the band gap energy values. The comparison of the energy levels locations of the electrodeposited poly(naphthalenediimide-quaterthiophene) derivative (e-PNDIT4) and P3HT thin films transferred b…

Highly Stable Thin Films Based on Novel Hybrid 1D (PRSH)PbX3 Pseudo-Perovskites

2021

In this study, the structure and morphology, as well as time, ultraviolet radiation, and humidity stability of thin films based on newly developed 1D (PRSH)PbX3 (X = Br, I) pseudo-perovskite materials, containing 1D chains of face-sharing haloplumbate octahedra, are investigated. All films are strongly crystalline already at room temperature, and annealing does not promote further crystallization or film reorganization. The film microstructure is found to be strongly influenced by the anion type and, to a lesser extent, by the DMF/DMSO solvent volume ratio used during film deposition by spin-coating. Comparison of specular X-ray diffraction and complementary grazing incidence X-ray diffract…

3D Nanoscopic Control of Ordered Molecular thin Films for Electronic Applications

2010

INCORPORATION OF METAL-PORPHYRIN DERIVATIVES IN TITANIA NANOSTRUCTURED 3D NETWORKS: THIN FILM PROPERTIES AND APPLICATIONS

2014

Organic Thin-Film Transistors with Enhanced Sensing Capabilities

2009

Organic thin-film transistors, used as sensing devices, have been attracting quite a considerable interest lately as they offer advantages such as multi parameter behaviour and possibility to be quite easily molecularly tuned for the detection of specific analytes. Here, a study on the dependences of the devices responses on important parameters such as the active layer thickness and its morphology as well as on the transistor channel length is presented. To introduce the least number of variables the system chosen for this study is quite a simple and well assessed one being based on a thiophene oligomer active layer exposed to 1-butanol vapours.

Bulk heterojunctions by boramers for plastic photovoltaics

2009

Size effects of static and dynamic polarization in ferroelectric thin film multilayers

2001

Abstract A thermodynamic theory for the calculation of static and dynamic polarization profiles of ferroelectric thin film multilayers is developed. The free energy functional is written down using a multilayer model in which c-domain layers of the ferroelectric material alternate with a-domain layers of a second ferroelectric materials. We assume that the interfaces are perfectly sharp and that the polarization at these boundaries is zero. The equilibrium polarization profile, its temperature and thickness dependencies were determined from the solutions of the Euler-Lagrange equations. A thickness induced ferroelectric phase transition is shown to exist and its transition temperature and c…

Physical properties of ferroelectric film with continuous space charge distribution

2014

We present a theory of ferroelectric phase transitions in a film with a homogeneously distributed space charge leading to the so-called built-in polarization. On the base of our complete solution of the problem of continuous space charge distribution in a ferroelectric film, we calculate the ferroelectric phase transition temperature , spatial polarization distribution in paraelectric and ferroelectric phases as well as hysteresis loop in the ferroelectric phase. We have shown that the presence of continuous space charge in a film inhibits the ferroelectricity in it: it lowers the ferroelectric phase transition temperature and coercive field. Our estimates of these differences show that the…

Photocurrent Spectroscopy Applied to the Characterization of Compositionally and Structurally Graded Materials: from Thin Films to Nanostructures

2010

Low-Temperature Atomic Layer Deposition of Crystalline and Photoactive Ultrathin Hematite Films for Solar Water Splitting

2015

We developed a low-temperature atomic layer deposition route to deposit phase pure and crystalline hematite (alpha-Fe2O3) films at 230 degrees C without the need for postannealing. Homogenous and conformal deposition with good aspect ratio coverage was demonstrated on a nanostructured substrate and analyzed by transmission electron microscopy. These as-deposited alpha-Fe2O3 films were investigated as photoanodes for photoelectrochemical water oxidation and found to be highly photoactive. Combined with a TiO2 underlayer and a low-cost Ni(OH)(2) catalyst, hematite films of less than 10 nm in thickness reached photocurrent densities of 0.3 mA cm(-2) at 1.23 V vs RHE and a photocurrent onset po…